Rare or elusive? A test of expert knowledge about rarity of Amazon forest birds

Abstract

Aim To offer a test of expert knowledge about rarity of twenty Amazon forest bird species following an approach that equates rarity with low site occupancy and formally accounts for imperfect species detection. We define ten pairs of closely related species, each pair with one hypothetically common and one hypothetically rare species. Our null hypothesis is that members of each pair have similar occupancy, with hypothesized differences due to detection errors alone.Location A 1000-ha plot of primary rainforest in the central Brazilian Amazon.Methods We visited each of 55 sampling sites multiple times per season for three field seasons and estimated the probability of site occupancy by each species following a maximum likelihood state-space approach that also estimates the probability that a species is present yet undetected at a site. To maximize detection and account for its variation, we employed three different sampling techniques while systematically training and testing observer's ability to recognize species.Results Occupancy estimates agree with expert predictions in all but two species pairs and show no evidence of clear temporal variation in occupancy between sampling seasons. Detection probability had a positive relation with observer ability, a strong relation to time of day across species, and a strong relation with the use of playback for some species. Detection with point counts and with autonomous recorders varied between species pairs. Main conclusions We reject the null hypothesis of equal occupancy within pairs, concluding that expert knowledge on species rarity is useful and worth eliciting. Our results replace qualitative ratings of rarity with statistical estimates of occupancy, establishing a reliable baseline for future comparisons. Besides illustrating the relevance of expert knowledge, this application to Amazonian birds illustrates a flexible approach that can be used for testing knowledge about rarity for a variety of species groups and spatial scales.

Real-time bioacoustics monitoring and automated species identification

“…Even if observers could stay in the field 24 hr/d throughout the year, there would still be a problem of observer bias (Cerqueira et al, in press). This is a major limitation especially when it is necessary to sample many sites simultaneously or when data are collected over many years by many different observers.…”

Modelling habitat persistence and impacts of management on the habitats of an endangered butterfly

“…Past studies have found experts to possess useful knowledge for conservation decision‐making in the absence of empirical information, but to also be less accurate than models developed from empirical data (e.g. Cerqueira et al ., ; McConnachie & Cowling, ; Aizpurua et al ., ; Drolet et al ., ), which could be seen in the variation of the responses of individual experts in our study. Though not significant, the negative association observed here between experts’ expectations of their knowledge and actual performance reflects a common finding in studies assessing expert performance (e.g.…”

Combining local knowledge and field surveys to determine status and threats to Timneh Parrots Psittacus timneh in Guinea-Bissau

“…In total, 69 interviews were conducted involving 207 people; participants were interviewed together in groups in some instances. Although data collected from local knowledge can be comparable to those collected using conventional methods (Danielson et al 2005, Jones et al 2008, Parry and Peres 2015), the characteristics of observers such as age (Turvey et al 2010) and experience (Cerqueira et al 2013) can influence ability to detect a species accurately. The sampling approach meant that all participants were men, as they were considered to have greater direct experience of parrot behaviour and ecology, since within local culture they typically spend a much greater proportion of their time engaged in activities in forested areas, and traditionally only men trap parrots.…”